1. Field of the Invention
This invention is generally directed to amphibious vehicles utilized in land reclamation and, more specifically, to a floatable lightweight vehicle which is supported and propelled by four independently driven generally hollow pods which are of sufficient size to provide the necessary buoyancy to allow the vehicle to float on water. Each of the pods includes a generally convex lower surface. A plurality of generally radially extending fins or cleats are disposed along the outer and lower surfaces of the pods for purposes of increasing traction and providing propulsion as the pods are rotated. The pods are adjustably mounted to outriggers which extend from a main frame so that the angle of inclination of the pods relative to a surface being traversed may be selectively adjusted to thereby vary the effective surface contact area of each pod. In the preferred embodiment, the pods are driven in opposite directions with respect to one another on opposite sides of the vehicle frame and in such a manner that the pods oriented diagonally with respect to the main frame are driven in the same direction.
2. History of the Related Art
In order to preserve the environment, it is necessary in areas where strip mining activities have occurred to reclaim the land by reworking and converting it back to its natural state, or an accepted alternative state, such as for recreational uses or wildlife sanctuaries. In the strip mining of phosphate and similar resources, the ore is conventionally mixed with water and pumped to processing plants where the ore is washed and graded before being further processed to remove the phosphate from the soil. During such processing, the water is conventionally discharged as a water/clay mixture into large settling ponds where the water is allowed to slowly seep into the soil. Settling ponds often embody vast acres of land which are bordered by dikes to retain the water/clay mixture and are generally capable of retaining multiple millions of gallons of water and discharged clay per day. As the ponds fill with clay, they are generally abandoned in favor of new ponds. Once abandoned, settling ponds must be reclaimed in order to preserve the environment by draining surface waters to allow the clay to settle and dry so that the earth may be reworked utilizing conventional equipment. In other mired areas, the surface contours must be reshaped and properly seeded to restore the land to its natural state. In some instances, marshy areas must be reestablished for wildlife refuge.
The use of conventional tractors and other related vehicles to reclaim settling ponds and other areas where strip mining has occurred has not proven to be satisfactory. Because such areas are unstable and incapable of supporting the weight of conventional vehicles, such vehicles become quickly bogged down in sand, slime and mud. In order to permit dredging, backhoe and other related earthworking equipment to be utilized in areas which include standing water and often are marshy or swamp-like, various types of off-road vehicles have been designed to permit some degree of vehicle operation. Some vehicle have large hollow tires to distribute the weight of a vehicle over a greater area of unstable soil or to provide some degree of buoyancy for the vehicle in areas where there is standing water or a high water table. Unfortunately, in some areas, it has been found that such vehicles are not satisfactory and they often become bogged down requiring that they be towed from the reclamation site. In addition, the maneuverability of such vehicles in terrains of poor ground stability is limited and, thus, not all areas of a site being reclaimed are accessible.
Other types of reclamation vehicles incorporate pontoons to provide increased buoyancy. This type of equipment is generally preferred in areas where there is standing water which is sufficiently deep to allow the vehicle to float, however, such units become bogged down in areas where there is a substantial amount of clay and limited surface water. Again, as with the oversized tire reclamation vehicles, pontoon type vehicles are restricted in their maneuverability in many types of soil conditions encountered in most land reclamation projects.